1980 Evinrude 35 horse

[Brandon76]

90 on the top cylinder 60 on the bottom. Some scarring on the bottom. Would a dingleberry hone work. It does run just trying to improve it.

 

[jimmbo]

Welcome to iboats

Dingleberry Hones are really not suitable for Engines that have Ports in the Cylinder Walls, the Balls, are under tension when in the bore, and will extend into the port, and damage both the ball and the Port. They also don't reveal the tapers in bore like the standard Hone will. Two strokes wear a differently that the cylinder in Four Stroke
With the compression numbers you gave, along with the mentioned Scoring, your engine likely needs to be bored Oversize,

 

[racerone]

Motor needs to come apart for proper repairs.

 

[jimmbo]

Motor needs to come apart for proper repairs.

My first thought was WTF, but I guess there have been some people who have tried to hone the Upper Cylinder Walls, with the Piston at BDC

 

[Brandon76]

Thanks

 

[racerone]

The piston / rings are damaged !!-----More required than honing !-----Piston ( likely O/S needed ) needs to be replaced.-----A donor motor / block is your best option.

 

[Brandon76]

I found a 77 35 h Block is running 120 top and bottom Everything else is rough hopefully I can use it. Compatible between a 77 and 80 35 h?

 

[jimmbo]

Compare parts lists for both engines, and looks for differences.